This invention relates generally to an improved process for preparing parfried and frozen potato products such as elongated French fry strips. More specifically, this invention relates to an improved production process for preparing parfried and frozen French fry potato products which exhibit substantially reduced crumb generation when finish prepared particularly as by finish fry preparation. The improved process is especially suited for parfrying and/or finish frying the potato products in an oil that is liquid (at room temperature) or substantially non-hydrogenated oil, such as a zero grams Trans Fat (ZGTF) oil, with dramatically reduced crumb generation while producing a finished product characterized by a highly desirable combination of taste, appearance and textural attributes.
Parfried and frozen potato products, such as elongated French fry strips, are widely available in the foods industry. These potato products are conventionally prepared by cutting whole potatoes into elongated strips of a desired size and shape, and then partially cooking the potato strips by blanching in hot water or steam. Thereafter, the potato strips are typically dewatered or partially dried, followed by partial frying, or parfrying, in hot cooking oil. The parfried potato strips are then frozen for packaging, shipping and/or storage. Prior to consumption, the parfried and frozen potato strips are reconstituted or finish prepared typically by finish frying in hot oil. French fried potato strips of this type are utilized extensively in restaurant and food service operations, and particularly in so-called fast food restaurants wherein it is desirable to produce a finish cooked product with a substantially optimized set of quality characteristics and with a relatively short finish fry preparation time. Further details of an exemplary French fry production process are described in U.S. Pat. No. 3,397,993, which is incorporated by reference herein.
More specifically, one major objective of potato processors is to provide parfried and frozen potato strips which can be finish prepared with a combination of taste, color, odor, and textural attributes selected for substantially optimum consumer palatability. For example, it is highly desirable to provide parfried and frozen potato strips which, after finish preparation, exhibit a light and tender but crispy exterior surface of golden brown fried color encasing a soft and mealy interior which is neither too dry nor too soggy. Moreover, especially in a fast food restaurant environment, it is important to provide finish cooked potato strips which can consistently retain these desired sensory qualities for an extended holding period of at least several minutes before actual consumption. In the past, achieving these desirable product qualities on a consistent basis has generally required that the potato strips be finish prepared by frying in hot oil. In a fast food establishment, to avoid advance preparation of potato strips that might not be sold or served within a limited holding time of several minutes, a relatively short finish fry step is desired and is typically on the order of about 1.5-3.5 minutes for smaller so-called shoestring size cut strips and about 3-4 minutes for larger strips cut sizes.
Generation of small crumbs particularly within the finish fry oil during finish fry strip preparation is a potentially major problem faced by a restaurant or food service operator. In this regard, it is generally known that a quantity of small crumbs is produced during finish frying, wherein these crumbs may tend to float within the hot finish fry oil. If allowed to accumulate, these crumbs can foul the oil and can adhere to the potato strips in a quantity and manner that detracts from the finish-prepared product.
The magnitude of crumb generation appears to be related to the type of cooking oil used for parfrying and/or for finish frying the potato strips. That is, with traditional hydrogenated or partially hydrogenated or highly saturated cooking oils which are solid or semi-solid at room temperature, crumb generation appears to be relatively moderate whereby routine oil filtering is normally sufficient to limit crumb accumulation to an acceptably low level. In a typical fast food restaurant, routine oil filtering has normally involved filtering of the cooking oil once each day. However, these traditional hydrogenated or partially hydrogenated and saturated cooking oils include fat constituents known as Trans Fats and saturated fats which do not meet the dietary standards and preferences of many modern consumers. As a result, significant interest has developed in liquid (at room temperature), substantially non-hydrogenated cooking oils referred to generally as zero grams Trans Fat (ZGTF) oils for producing French fried potato strips. See, e.g., U.S. Publication 2004/0146626 (now U.S. Pat. No. 7,169,430), which is also incorporated by reference herein, for an exemplary ZGTF oil. But when used for French fry production, these ZGTF oils are accompanied by dramatically increased generation of crumbs during the finish fry step. Routine (once per day) filtering of the finish fry oil is unable to prevent crumb accumulation to an unacceptably high magnitude. Instead, it is necessary for the restaurant or food service personnel to filter or skim accumulated crumbs from the finish fry oil on a frequent schedule, approximately 1-2 times per hour, following a small number of cooking cycles. Historically, requiring such labor-intensive activity and/or a change in finish fry procedures at the restaurant or food service operator facility is highly undesirable, and results at best in a finish-prepared product of inconsistent quality characteristics.
The reasons for crumb generation, and the differential rates of crumb generation for different types of cooking oils, are not well understood. Some have theorized that crumbs are produced during parfrying, wherein crumb accumulation in the finish fry oil can be reduced by separating generated crumbs from the parfried strips before freezing. In this regard, post-parfry water wash systems of the type used in the past for washing and recovering excess oil from the parfried strips have been suggested for crumb control use. These post-parfry water wash systems have utilized a heated and relatively high volume water or steam overspray, sometimes in combination with an air spray, to scrub oil from the outer surfaces of the parfried strips. The combined water-oil effluent is then subjected to a separator step to recover and recycle the oil. When used for crumb control, these post-parfry water wash systems have demonstrated a substantial reduction in crumb generation rate, but they have also been accompanied by a substantial deterioration in product quality characteristics after finish frying. In addition, such water wash systems significantly increase overall French fry production complexity which can have a negative impact on costs.
Despite this crumb generation issue, there is a strong trend in the foods industry to move toward wide-scale adoption of ZGTF oils for parfrying and finish frying French fry potato products, such as French fry strips. Accordingly, there exists a strong need for an improved French fry production process which can effectively and economically reduce and control crumb generation without adversely impacting product quality characteristics after finish frying. Moreover, there exists a need for implementation of such improved process at a production facility, in the course of parfrying and freezing the potato strips, so that the restaurant or food service operator can finish prepare high quality French fry products without requiring any change in normal finish fry procedures. The present invention fulfills all of these needs, and provides further related advantages.